Elevator control apparatus

ABSTRACT

An apparatus for selecting the floor, and slowing down and stopping an elevator is described. The apparatus comprises first and second wires vertically mounted in an elevator shaft. The first wire has a plurality of level cams and a plurality of stepping cams alternatively mounted along its length. The second wire has a plurality of slow down cams mounted along its length. The wires and cams pass through appertures in a control box which houses a stepping switch operated by the stepping cams, a pair of micro switches operated by the leveling cams, and a further micro switch operated by the slow down cams. The slow down and leveling cams have conically shaped ends which provide for ease of movement through the control box while the stepping cams have blunt ends which easily pass through the control box yet impinge on the stepping switch for activation purposes.

United States Patent [191 Richmon Primary Examiner-Bernard A. Gilheany Assistant Examiner-W. E. Duncanson, Jr. Attorney-B. Franklin Griffin, Jr. et al.

[ @ct. R6, 1973 [5 7] ABSTRACT An apparatus for selecting the floor, and slowing down and stopping an elevator is described. The apparatus comprises first and second wires vertically mounted in an elevator shaft. The first wire has a plurality of level cams and a plurality of stepping cams alternatively mounted along its length. The second wire has a plurality of slow down cams mounted along its length. The wires and cams pass through appertures in a control box which houses a stepping switch operated by the stepping cams, a pair of micro switches operated by the leveling cams, and a further micro switch operated by the slow down cams. The slow down and leveling cams have conically shaped ends which provide for ease of movement through the control box while the stepping cams have blunt ends which easily pass through the control box yet impinge on the stepping switch for activation purposes.

8 Claims, 4 Drawing Figures BACKGROUND OF THE INVENTION This is a continuation-in-part of U.S. Pat. application Ser. No. 19,318, filed Mar. 13, 1970 now U.S. Pat. No. 3,674,l l3, and entitled -Automatic Elevator Stopping Apparatus. In accordance with a notice in volume 859, page 346 of the Official 1969, the subject matter of application Ser. No. 19,318 is incorporated'herein by reference.

The referenced application, as well as this invention, relate generally to an elevator control apparatus suitable for controlling the floor selection, slow down and stopping of elevators, or similar devices, adapted for movement between predetermined stopping positions.

Reference is made to U.S. Pat. application Ser. No. 19,318 for a discussion of prior art automatic elevator control and stopping apparatus. While an automatic elevator stopping apparatus of the type described in the referenced patent application is found to be satisfactory in solving any of the disadvantages of prior art elevator stopping and control systems that perform the same function, there are certain areas still subject to improvement. For example, it is possible for the apparatus described in the referenced patent application to be offset by one or more floors under one set of operative conditions. More specifically, the automatic elevator stopping apparatus described in the referenced application includes two control cams for each floor. These control cams have conical ends facing one another. The other ends of the control cams are blunt. The blunt ends control the rotation of a star switch mechanism. That is, when a blunt end impinges on an arm of the star switch mechanism it causes the switch to rotate. On the other hand, when a conical end impinges on an arm of the star switch, the switch does not rotate because the conical end spreads a pair of fingers making up the arm in a manner that allows the control cam to pass therebetween.

The foregoing aparatus is eminently satisfactory if the elevator moves continuously from floor to floor before reversing directions. However, if the elevator moves to a position between floors such that it passes an entire set of cams but does not pass the first cam of the next set of cams, and then reverses direction, it fails to rotate the star switch. Thereafter, the elevator is offset by one floor. It can be offset by more than one floor should the same situation occur in the same direction as the first occurrence. Contrawise, correction will occur if the elevator has the same situation occur in the opposite direction.

The foregoing problem is compensated for in the apparatus described in the referenced patent application because the entire mechanism is reset each time the elevator reaches the bottom (or top) floor. However,

should the elevator run for a number of operations between intermediate floors after the foregoing event occurs, such operation would continue to bring the elevator to the wrong floor. Hence, it is desirable to provide a system that alleviates this condition, yet maintains the ease of operation of a system wherein a plurality of cams are utilized to control the movement of an elevator mechanism or the like.

Therefore, it is an object of this invention to provide a new and improved elevator control mechanism that eliminates the necessity for a correction device.

Gazette dated Feb. 11, 7

It is another object of this invention to provide a new and improved elevator control mechanism that includes a mechanism which prevents the erroneous stepping of a stepping switch utilized to control an elevator.

It is a further object of this invention to provide a new and improved elevator control apparatus that includes a plurality of cams adapted to control the between floor movement of an elevator, the slow down of the elevator and the stopping of the elevator at a floor level position.

SUMMARY OF THE INVENTION In accordance with principles of this invention, a control box and a pair of wires having cams mounted thereon are movable with respect to one another. One wire contains step cams and level cams located intermediate to one another. The other wire includes slow down cams. The cams coact with. switches located in. the control box to control the positioning, slow down and stopping of an elevator or other similar structure attached to either the control box or the wires.

In accordance with further principles of this invention, a star switch is mounted inside of the control box and has arms which coact with the step'cams, but which allow the level cams to pass thereby without rotation of the star switch. In addition, a pair of micro switches, located on either side of the star switch, are controlled by the level cam so that the elevator is stopped at a position where the floor of the elevator is level with a floor of the building housing the elevator. In addition, a further micro switch is mounted in the switch housing and coats with the slow down cams so as to generate a portion of a slow down signal as the elevator approaches a floor. This portion of a slow down signal combines with the balance of the slow down signal generated by a car call or hall call signal in the elevator controller to cause a complete slow down signal at the desired floor.

In accordance with still further principles of this invention, the step cams are blunt on either end so that a positive rotation of the star switch occurs each time a step cam impinges on an arm of the switch. Moreover, the step cams are located intermediate the floor level positions so as to prevent erroneous rotation of the star switch.

It will be appreciated by those skilled in the art and others from the foregoing summary of the invention that a new and improved apparatus for controlling an elevator is provided. The carn arrangement and nature overcome the disadvantages of the referenced U.S. patent application because a single stepping cam, rather than two stepping cams are utilized for each floor position. Furthermore, the advantages of the referenced application are maintained in that a leveling cam is still allowed to pass the star switch without causing the operation thereof yet is useful for leveling purposes. Moreover, slow down cams are still provided so that slow down signals can be used to control the slowing of the elevator prior to the stopping thereof.

BRIEF DESCRIPTION OF THE DRAWINGS I FIG. 1 of the interior of the control box;

FIG. 3 is a cross-sectional diagram along line 3-3 of FIG. 1 of the interior of the control box; and,

FIG. 4 is a perspective view of a preferred embodiment of a step cam.

DESCRIPTION OF THE PREFERRED EMBODIMENT Turning now to the drawings, FIG. 1 illustrates a vertically mounted T-shaped channel member 11. As will be understood by those skilled in the art, T-shaped channel member 11 is mounted in an elevator shaft (not shown) in a manner such that a vertical U-shaped channel 13 attached to a pair of U-shaped support channels 15 and 17 rides over the leg of the T. More specifically, support channels 15 and 17 support an elevator cab (not shown) by Mounted between these channels is the U-shaped vertical channel 13. The mounting is such that the interior of the U faces the leg of the T-shaped channel 11. This manner of mounting allows the T-shaped channel to generally maintain the elevator cab in the center of the elevator shaft thereby preventing rubbing of the sides of the elevator cab against the sides of the elevator shaft.

Attached to one of the support channels 15 is an L- shaped support member 19 which is attached to and supports a control box 21. Mounted on the upper end of the T-shaped channel is an upper outwardly projecting bar 23 and mounted on the lower end of the T- shaped channel is a lower outwardly projecting bar 25. Stretched between the upper bar 23 and the lower bar 25 are first and second wires 27 and 29 and first and second tension springs 31 and 33. The tension springs 31 and 33 allow the wires to be tauntly stretched between the upper and lower bars 23 and 25.

For purposes of discussion, the elevator is assumed to be mounted in a three floor elevator shaft. Thus, the elevator can stop at a top floor, an intermediate or middle floor and a lower floor. However, it will be appreciated by those skilled in the art and others that this limitation on the number of floors is merely for purposes of description and that there can be more than one intermediate floor.

Thefirstwire 27 supports three level earns 35, 37 and 39. The three level cams correspond to the upper floor, the lower floor and the middle floor. Intermediate the upper floor level cam 35 and the middle floor level cam 37 is a first step cam 41 and intermediate the intermediate floor level cam'-37 and the lower floor level cam 39 is a second step'cam 43. The step cams (best seen in FIG. 4) have blunt shaped ends and the level cams have conically shaped ends. These cams are shaped in these particular manners so that they can perform their respective functions, best illustrated in FIG. 2. More specifically, one arm 45 of astar switch of the type described in referenced patent application Ser. No. 19,318 is'illustrated in FIG. 2. The arm is formed of a pair of finger elements 45a and 45b. The finger elements 45a and 45b are preferably formed of spring steel and have outwardly projecting flanges on either side. The finger elements are located, and separated by a predetermined distance such that the level cams 35,

37, and 39 pass between the arm 45 without applying friction to the finger elements sufficient to rotate the star switch. On the other hand, the blunt ends of the step cams 41 and 43 engage like gears to rotate the star switch. Rotation of the star switch provides, of course. an indication that the elevator attached to the control box 21 is passing the position of the particular step cam operating the star switch.

In addition to the arm 45 of the star switch, a pair of micro switches 47 and 49 are mounted, one on eitherside of the switch arm 45, in positions such that the control arms 51 and 53 of the first and second micro switches can both be opened at the same time by a level cam. More specifically, the arm 51 of the first or upper micro switch 47 is located above the switch arm 45 and the arm 53 of second or lower micro switch is located below the switch arm 45. Both arms are located adjacent to the first wire 27 but separated therefrom by a distance such that the arms are not moved by the first wire 27 but are moved by the cams mounted on the first wire. The level cams are relatively long. The length of the level cams is such that the upper conical end just opens the upper micro switch 47 by moving its arm 51 when the lower conical end is in a position such that it just opens the lower micro switch 49 by moving its arm. If the level cam is either above or below this exact position one micro switch is open and the other is closed. Or, if no part of the level cam is between the arms of the micro switches both of them are open.

Suitably positioning the level cams on the first wire allows both micro switches to be open when the floor of the elevator cab is level with the desired floor. When this occurs, the micro switches can prevent the application of power to the elevator drive. Thus, level control is provided. An uncomplicated way for the micro switches to carry out this function is for them to be connected in parallel with the parallel connection being connected in series with the power source. Alternatively, more complicated arrangements can be used. Also, the micro switch arrangement could be reversed, i.e., both switches closed rather than open when the level cams are in the level position. Even though this latter arrangement is not as fail safe as the former arrangement, it can be used. If so, a somewhat different electrical circuit, apparent to those skilled in the art, must be used. I

Mounted on thesecond wire 29 are a plurality of slow down cams 55, 57, 59, and 61. The upper and lower slow down earns 55 and 61 are adapted to control slow down as the elevator cab approaches the upper and lower floors. The intermediate slow down cams 57 and 59 are mounted on either side of the level cam 37 relating to the intermediate floor and control slow down as the elevator cab approaches the intermediate floor from either the upper or the lower direction. The slow down cams control a micro switch 63, illustrated in FIG. 3. The micro' switch is mounted such that its arm is .moved each time a slow down cam passes through the control box 21. When the micro switch is thus closed a slow down signal is generated which causes slow down of the elevator cab provided, of course, the slow down cam relates to the floor chosen by the elevator selector switch (not shown). Thus, as the elevator approaches a particular floor, it slows down until it is stopped in the level position controlled by the appropriate level cam 35, 37 or 39.

It will be appreciated from the foregoing description that a control apparatus suitable for use in controlling the positioning, slow down and stopping of an elevator is provided by the invention. Because a single step cam intermediate each pair of floors rather than two cams on the general level of each floor are used, a positive action must occur as the elevator moves through a predetermined point to change the position of the star switch. Thus the possibility of the erroneous occurrence previously described with regard to US. Pat. application Ser. No. 19,318 is eliminated. in addition, a level mechanism and a slow down mechanism is provided by the invention.

While a preferred embodiment of the invention has been illustrated and described, it will be appreciated by those skilled in the art and others that various changes can be made therein without departing from the spirit and scope of the invention. For example, the switch box can be affixed to the wall of an elevator shaft and the first and second wires, having cams mounted thereon, affixed to the elevator so that the same relative movement results, yet the wires move, not the control box. Hence, the invention can be practiced otherwise than as specifically described herein.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An elevator apparatus suitable for sensing the movement of an elevator in a multi-floor building and suitable for controlling the leveling of the elevator with respect to the, floors of said multi-floor elevator control apparatus comprising:

a first wire;

a plurality of generally cylindrical level cams conically shaped at both ends, said plurality of generally cylindrical level cams equal in number to the floors of said multi-floor building, said plurality of generally cylindrical level cams being mounted on said first wire;

a plurality of generally cylindrical step cams blunt at both ends, said plurality of generally cylindrical step cams being one less in number than the number of floors of said multi-floor building, said plurality of generally cylindrical step cams being mounted on said first wire in a manner such that said level cams and said step cams alternate along the longitudinal length of said wire with one of said level cams'starting said alternate array and another of said level cams ending said alternate array;

a control box having apertures which allow said first wire and said-plurality of level cams and step cams to pass through said control box;

a multiple position switch located in said control box so as to be impinged upon by the blunt ends of said building, said 6 step cams, said impingement causing said multiple position switch to be moved from one position to another position of a multitude of predetermined positions, the positioning of said multiple position switch being related to the position of said elevator in said multi-floor building; and,

a level switch means mounted in said control box so as to be impinged upon by said plurality of level cams, said level switch means adapted to control the leveling of said elevator with respect to the floors of said multi-floor building.

2. An elevator control apparatus as claimed in claim 11, wherein said multiple position switch comprises a star switch having arms that are moved by the blunt ends of said plurality of step cams, and wherein said level switch means comprises first and second micro switches controlled by said level cams, said micro switches being mounted in said control box in positions such that said level cam places both micro switches in the same electrical state when said level cam is in a predetermined position within said control box.

3. An elevator control apparatus as claimed in claim 2 including:

a second wire; and,

a plurality of slow down cams mounted on said second wire, said control box having a second aperture which allows said second wire and said plurality of slow down cams to pass therethrough.

4. An elevator control apparatus as claimed in claim 3 wherein said switch means includes a further micro switch mounted so as to be activated by the slow down cams mounted on said second wire.

5. An elevator control apparatus as claimed in claim 4 wherein said first and second wires are fixedly mounted and wherein said control box is attached to said elevator so that said box moves relative to said first and second wires as said elevator moves.

6. An elevator control apparatus as claimed in claim 11 including:

a second wire; and,

a plurality of slow down cams mounted on said second wire, said control box having a second aperture which allows said second wire and said plurality of slow down cams to pass therethrough.

7. An elevator control apparatus as claimed in claim 6 wherein said switch means includes a further micro switch mounted so as to be activated by the slow down cams mounted on said second wire.

8. An elevator control apparatus as claimed in claim 7 wherein said first and second wires are fixedly mounted and wherein said control box is attached to said elevator so that said box moves relative to said first and second wires as said elevator moves. 

1. An elevator apparatus suitable for sensing the movement of an elevator in a multi-floor building and suitable for controlling the leveling of the elevator with respect to the floors of said multi-floor building, said elevator control apparatus comprising: a first wire; a plurality of generally cylindrical level cams conically shaped at both ends, said plurality of generally cylindrical level cams equal in number to the floors of said multi-floor building, said plurality of generally cylindrical level cams being mounted on said first wire; a plurality of generally cylindrical step cams blunt at both ends, said plurality of generally cylindrical step cams being one less in number than the number of floors of said multifloor building, said plurality of generally cylindrical step cams being mounted on said first wire in a manner such that said level cams and said step cams alternate along the longitudinal length of said wire with one of said level cams starting said alternate array and another of said level cams ending said alternate array; a control box having apertures which allow said first wire and said plurality of level cams and step cams to pass through said control box; a multiple position switch located in said control box so as to be impinged upon by the blunt ends of said step cams, said impingement causing said multiple position switch to be moved from one position to another position of a multitude of predetermined positions, the positioning of said multiple position switch being related to the position of said elevator in said multi-floor building; and, a level switch means mounted in said control box so as to be impinged upon by said plurality of level cams, said level switch means adapted to control the leveling of said elevator with respect to the floors of said multi-floor building.
 2. An elevator control apparatus as claimed in claim 11, wherein said multiple position switch comprises a star switch having arms that are moved by the blunt ends of said plurality of step cams, and wherein said level switch means comprises first and second micro switches controlled by said level cams, said micro switches being mounted in said control box in positions such that said level cam places both micro switches in the same electrical state when said level cam is in a predetermined position within said control box.
 3. An elevator control apparatus as claimed in claim 2 including: a second wire; and, a plurality of slow down cams mounted on said second wire, said control box having a second aperture which allows said second wire and said plurality of slow down cams to pass therethrough.
 4. An elevator control apparatus as claimed in claim 3 wherein said switch means includes a further micro switch mounted so as to be activated by the slow down cams mounted on said second wire.
 5. An elevator control apparatus as claimed in claim 4 wherein said first and second wires are fixedly mounted and wherein said control box is attached to said elevator so that said box moves relative to said first and second wires as said elevator moves.
 6. An elevator control apparatus as claimed in claim 11 including: a second wire; and, a plurality of slow down cams mounted on said second wire, said control box having a second aperture which allows said second wire and said plurality of slow down cams to pass therethrough.
 7. An elevator control apparatus as claimed in claim 6 wherein said switch means includes a further micro switch mounted so as to be activated by the slow down cams mounted on said second wire.
 8. An elevAtor control apparatus as claimed in claim 7 wherein said first and second wires are fixedly mounted and wherein said control box is attached to said elevator so that said box moves relative to said first and second wires as said elevator moves. 